Distributor: energy jumps two air gaps, one at low pressure, one at high pressure, energy is lost to both jumps, moisture can cause the energy to be dissipated into wrong places too.

Wasted spark: energy jumps two gaps, but one is full of high pressure air, and the other highly ionised exhaust gas. This latter jump is effectively a dead short, so the in-cylinder gap receives almost all of the spark energy.

COP/CNP: energy only jumps one gap, all energy is delivered to the plug gap itself, and short of part failure, the spark WILL jump in the cylinder, even if at a sub-optimal time due to insufficient voltage when desired.

This is on top of the dwell issues.

Note, both wasted and COP/CNP are also much lower maintenance than a distributor. Neither have wear and tear parts (except the plugs) and typically only the leads (and/or carbon rods) themselves degrade slowly with time and heat cycles. A distributor has multiple parts to wear out and fail, even if it's a modern electronic one.

This is data from the user "russian" who measured his OEM setup in some way. It clearly shows two things, more dwell at low RPM where duty is low, and voltage potentially low, and less dwell at high RPM when it's running out of time.

At the top end you can see the ECU pulling dwell back to allow sufficient spark time:

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